The present invention relates to the new and distinct x Mangave hybrid plant, x Mangave ‘Sponge Paint’ that was hybridized by the inventor at a wholesale perennial nursery in Zeeland, Mich., USA as a cross between a proprietary, unreleased hybrid selection of x Mangave assigned the breeder code 12-6-4 (not patented) as the female or seed parent times and Agave potatorum ‘Bluewinds’ (not patented) as the male or pollen parent. The cross was performed Nov. 17, 2014 and seeds were harvested and sown later the following spring. Through trials at the same nursery the plant was assigned the breeder code 15-47-23. The new plant has been successfully asexually propagated by removal of basal offsets and sterile shoot-tip tissue culture at the same nursery in Zeeland, Mich. The asexual tissue culture propagation has been found to produce stable and identical plants that maintain all the unique characteristics of the original plant.
BRIEF SUMMARY OF THE INVENTION
‘Sponge Paint’ differs from its parents as well as all other Manfreda, Agave and x Mangave known to the applicant. The female parent has a more upright habit with longer, arching, narrower and thinner leaves with more burgundy spots. The male parent is shorter and more compact in habit with foliage that is shorter, more obovate, has a creamy white margin and lacks the greyed-purple spotting on the upper and lower surfaces. The nearest comparison plants are: ‘Tooth Fairy’ U.S. Plant Pat. No. 29,599, ‘Purple People Eater’ U.S. Plant Pat. No. 29,949 and ‘Moonglow’ U.S. Plant Pat. No. 29,195. ‘Tooth Fairy’ has a taller habit, narrower foliage with larger teeth and apical spines and without greyed-purple spotting. ‘Purple People Eater’ has larger less compact habit, the foliage is slightly folded longitudinally, the marginal teeth are semi-flexible and more greyed-orange, and the leaves have a glaucous greenish-purple as well as spotted with greyed-purple. ‘Moonglow’ has flatter habit, narrower foliage with larger greyed-purple spotting.
‘Sponge Paint’ is unique from all of the above cultivars and all Agave, x Mangave and Manfreda known to the inventor by the following combined traits:                1. Rounded mound of oblanceolate to rhombic, sarcous, scabridulose leaves;        2. Leaves develop a silver-gray coloration with small wine-colored spots with strong ultraviolet light;        3. Leaf margins have medium-sized, sharp, firm, outward to slightly-recurved, marginal teeth and a long, firm, sharp apical spine;        4. Moderate growth rate;        5. Foliage is outwardly with distal portion slightly upwardly.        